ISSN:
1572-9540
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract We report new limits on right-handed currents, based on precise measurements of the endpoint of the e+ spectrum fromμ + decay. Highly polarizedμ + from the TRIUMF “surface” beam were stopped in pure metal foils within either an 1.1-T spin-holding logitudinal field, or a 70-gauss spin-precessing transverse field. Decay e+ emitted within 200 mrad of the beam direction were momentum-analyzed to ±0.2%. For the spin-held data, decay via (V-A) currents requires the e+ rate to approach zero in the beam direction at the endpoint. Measurement of this rate sets the 90%-confidence limits ξP μδ/ϱ〉0.9959 and M(WR)〉380 GeV, where WR is the possible right-handed gauge boson. For the spin-precessed data we independently determine a 90% confidence limit ξP μδ/ϱ〉0.9918.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02066134
Permalink